Homeostasis refers to the ability or tendency of an organism or a cell to maintain internal equilibrium by adjusting its physiological processes to maintain equilibrium or stability in the normal physiological states of the organism. In cardiac patients, homeostasis can involve maintaining a constant condition of appropriate fluid and electrolyte loads within and outside of the cells of the patient's heart. Potassium, for example, which is a necessary electrolyte of the heart, facilitates nerve impulse conduction and the contraction of the heart, along with cell membrane function and proper enzyme activity. Hypokalemia is a condition in which there are below normal levels of potassium in the blood serum, while hyperkalemia is a condition in which there are above normal levels of potassium in the blood serum. Both hyperkalemia and hypokalemia can occasionally provoke or indicate cardiac arrhythmias. Therefore, it is important that potassium levels be kept in a proper (homeostatic) balance for the maintenance of cardiac health. What is needed is a method and apparatus for monitoring of cardiac homeostasis to more effectively enable the earliest detection and accurate monitoring of potentially life-threatening arrhythmia conditions and/or progressive cardiac disease states.